Metal azo pigments

ABSTRACT

The novel yellow metal azo pigments based on at least three metal azo compounds, which differ at least in the type of metal, have improved colour strengths and are of excellent suitability for pigmentation of pigment preparations for a broad field of use.

The present invention relates to novel yellow metal azo pigments basedon at least three metal azo compounds which differ at least in the typeof metal, to processes for production thereof and to the use thereof asyellow pigment in pigment preparations.

BACKGROUND INFORMATION

The preparation of metal complexes from azobarbituric acid with nickelsalts and the use thereof as yellow pigments has long been known and hasbeen described many times in the literature (cf., for example, W.Herbst, K. Hunger: Industrial Organic Pigments, 3rd edition 2004, p.390/397). It is additionally known that these products can be reactedfurther, for example with melamine or melamine derivatives, in order toimprove the performance properties of the pigments, for example in thecolouring of plastics, lacquers and colour filters for LCDs.

In addition, the literature states that colouristic properties can alsobe adjusted using, apart from nickel salts, one or more salts ofdifferent metals as well. The application EP-A 1 591 489 describes metalcomplexes of azo compounds containing, as metals, those from the groupof the alkali metals, alkaline earth metals, the lanthanoids, andaluminium, scandium, titanium, vanadium, chromium, manganese, cobalt,copper, nickel and zinc, and optionally iron. The pigments obtained havea different colour locus compared to the pure nickel-azobarbituric acidcomplexes.

Controlled surface coverage of the metal azo pigment can likewiseachieve an improvement in performance-based properties, specifically thelowering of the dispersion hardness as a measure of the dispersionproperties of the pigment. However, this method of improvingdispersibility is associated with a reduction in the colour intensity ofthe pigment, which is directly dependent on the concentration ofcovering agent.

A further means of adjusting performance-based properties is to subjectthe pigments produced from nickel-azobarbituric acid complexes withmelamine, for example, to a heat treatment. This process step isassociated with a controlled alteration in the particle size of thepigments and the specific surface area thereof. This process isdescribed, for example, in EP-A 0 994 162.

EP-A 2682434 likewise discloses metal azo pigments based on nickel- andzinc-azobarbituric acid and melamine, which can be used as yellowcomponent in colour filters and have improved colouristic properties.

The metal azo pigments known from the prior art are still in need offurther improvement with regard to the performance features thereof.

SUMMARY OF THE INVENTION

It has been found that metal azo pigments based on azobarbituric acid,zinc and nickel salts and melamine and/or melamine derivatives and atleast one further metal salt other than zinc and nickel saltssurprisingly have an improved colour strength. The improvement of theseproperties enables improved use of these products, inter alia, forcolouring of plastics and lacquers, and for use in inkjets and as acomponent of colour filters for LCDs.

DETAILED DESCRIPTION OF THE INVENTION

The invention therefore relates to metal azo pigments, characterized inthat they comprise the following components:

-   a) at least three metal azo compounds which differ at least in the    type of metal and which each contain    -   structural units of the formula (I), or the tautomeric forms        thereof,

in which

-   -   R¹ and R² are each independently OH, NH₂ or NHR⁵,    -   R³ and R⁴ are each independently ═O or ═NR⁵,    -   R⁵ is hydrogen or alkyl, preferably C₁-C₄-alkyl,    -   and    -   Ni²⁺ and/or Zn²⁺ ions and at least one further metal ion ME,    -   where    -   Me is a di- or trivalent metal ion selected from the group of        Cu²⁺, Al³⁺, Fe²⁺, Fe³⁺, Co²⁺ and Co³⁺,    -   with the proviso that the amount of Zn²⁺ and Ni²⁺ ions together        is 70 to 95 mol % and the amount of metal ions Me is 5 to 30 mol        %, the amount of Zn²⁺ and Ni²⁺ ions together preferably being 70        mol % to less than 95 mol % and the amount of metal ions Me        being more than 5 mol % to 30 mol %, based in each case on one        mole of all metal ions in the metal azo pigment,    -   and    -   where the molar ratio of Zn²⁺ to Ni²⁺ ions in the metal azo        pigment is 92:5 to 5:92, preferably 70:10 to 10:70 and more        preferably 60:25 to 25:60,    -   and

-   b) at least one compound of the formula (II)

-   -   in which    -   R⁶ is hydrogen or alkyl, preferably C₁-C₄-alkyl optionally mono-        or polysubstituted by OH.

Preferably, in formula (I), R¹ and R² are each independently OH, NH₂ oran NHR⁵ radical where R⁵ is hydrogen or C₁-C₄-alkyl.

Preferably, in formula (I), R³ and R⁴ are each independently ═O or ═NR⁵where R⁵ is hydrogen or C₁-C₄-alkyl.

More preferably, in formula (I), R¹ and R² are OH and R³ and R⁴ are ═O.

Preferably, in formula (II), R⁶ is hydrogen or C₁-C₄-alkyl optionallymono- or polysubstituted by OH. More preferably, in formula (II), R⁶ ishydrogen.

Based on one mole of all metal ions present in the metal azo pigment,the amount of Zn²⁺ and Ni²⁺ ions together is generally 70 to 95 mol %and the amount of metal ions Me 5 to 30 mol %; the amount of Zn²⁺ andNi²⁺ ions together is preferably 70 mol % to less than 95 mol % and theamount of metal ions Me more than 5 mol % to 30 mol %, the amount ofZn²⁺ and Ni²⁺ ions together is more preferably 70 to 94 mol % and theamount of metal ions Me 6 to 30 mol %, the amount of Zn²⁺ and Ni²⁺ ionstogether is very preferably 75 to 90 mol % and the amount of metal ionsMe 10 to 25 mol %, and the amount of Zn²⁺ and Ni²⁺ ions together isespecially 80 to 85 mol % and the amount of metal ions Me 15 to 20 mol%.

The molar ratio of Zn²⁺ to Ni²⁺ ions in the metal azo pigment isgenerally 92:5 to 5:92, preferably 70:10 to 10:70 and more preferably60:25 to 25:60.

Substituents in the definition of alkyl denote, for example,straight-chain or branched C₁-C₆-alkyl, preferably straight-chain orbranched C₁-C₄-alkyl, which may optionally be mono- or polysubstitutedidentically or differently, for example by halogen such as chlorine,bromine or fluorine; —OH, —CN, —NH₂ or C₁-C₆-alkoxy.

Said metal ions Me are preferably in their most stable oxidation states.

In general, Me is a di- or trivalent metal ion selected from the groupof Cu²⁺, Al²⁺, Fe²⁺, Fe²⁺, Co²⁺ and Co²⁺.

Preferably, Me is a di- or trivalent metal ion selected from the groupof Cu and Al.

In the case that the metal azo compounds of component a) containdivalent metal ions ME, the structural units of the formula (I) and themetal ions Me can be regarded as complexes, for example those of theformula (Ia)

However, it is also possible that the metal ion is bonded via thenitrogen atoms in a tautomeric notation of the formula (Ia).

The same formula representation can be applied to the structural unitsof the formula (I) with the Zn²⁺ ions or with the Ni²⁺ ions. Thisrepresentation serves merely for illustration and does not make anyclaim to scientific correctness.

In the case that Me is a trivalent metal ion, the charge is balancedpreferably by an equivalent amount of anionic structural units of theformula (I).

Preferably, the charge of the doubly negatively charged structural unitsof the formula (I) is balanced to an extent of 80% to 100%, morepreferably to an extent of 95% to 100% and most preferably to an extentof 99.9% to 100% by the sum total of all Zn²⁺ and Ni²⁺ present in themetal azo pigment and further metal ions Me.

Preferably, the said metal azo compounds of components a) form adductswith components b), i.e. the compounds of the formula (II).

Adducts are understood here to mean molecular assemblies in general. Thebond between the molecules here may be the result, for example, ofintermolecular interactions or Lewis acid-base interactions or ofcoordinate bonds.

The term “adduct” in the context of the present invention shallgenerally encompass all kinds of intercalation and addition compounds.

The terms “intercalation compound” or “addition compound” in the contextof the present invention shall be understood, for example, to meancompounds which are formed on the basis of intermolecular interactionssuch as van der Waals interactions or else Lewis acid-base interactions.The way in which the intercalation proceeds here depends both on thechemical properties of the component to be intercalated and on thechemical nature of the host lattice. Compounds of this kind arefrequently also referred to as intercalation compounds. In a chemicalsense, this is understood to mean the intercalation of molecules andions (less commonly atoms as well) into chemical compounds.

This shall additionally also be understood to mean inclusion compoundscalled clathrates. These are compounds of two substances, one of whichis a guest molecule intercalated into a lattice or cage composed of ahost molecule.

The terms “Intercalation compound” or “addition compound” in the contextof the present invention shall also be understood to mean mixedintercalation crystals (including interstitial compounds). These arechemical non-stoichiometric crystalline compounds composed of at leasttwo elements.

In addition, the terms “intercalation compound” or “addition compound”in the context of the present invention shall also be understood to meancompounds which are formed on the basis of coordinate bonds or complexbonds. Compounds of this kind refer, for example, to mixed substitutioncrystals or mixed replacement crystals in which at least two substancesform a common crystal and the atoms of the second component are atregular lattice sites of the first component.

Preference is given to metal azo pigments comprising the adducts of

-   -   a) at least three metal azo compounds which differ at least in        the type of metal and which each contain structural units of the        above-specified formula (I)        -   in which R¹ and R² are OH,        -   and        -   R³ and R⁴ are ═O,        -   and        -   Ni²⁺ and/or Zn²⁺ ions and at least one further metal ion Me,    -   where    -   Me is a di- or trivalent metal ion selected from the group of        Cu²⁺, Al³⁺, Fe²⁺, Fe³⁺, Co²⁺ and Co³⁺,        with the proviso that the amount of Zn²⁺ and Ni²⁺ ions together        is 70 to 95 mol % and the amount of metal ions Me is 5 to 30 mol        %, the amount of Zn²⁺ and Ni²⁺ ions together preferably being 70        mol % to less than 95 mol % and the amount of metal ions Me        being more than 5 mol % to 30 mol %, the amount of Zn²⁺ and Ni²⁺        ions together more preferably being 70 to 94 mol % and the        amount of metal ions Me being 6 to 30 mol %, the amount of Zn²⁺        and Ni²⁺ ions together preferably being 75 to 90 mol % and the        amount of metal ions Me being 10 to 25 mol %, and the amount of        Zn²⁺ and Ni²⁺ ions together especially being 80 to 85 mol % and        the amount of metal ions Me being 15 to 20 mol %,        based in each case on one mole of all metal ions in the metal        azo pigment,    -   and    -   where the molar ratio of Zn²⁺ to Ni²⁺ ions in the metal azo        pigment is 92:5 to 5:92, preferably 70:10 to 10:70 and more        preferably 60:25 to 25:60,    -   and    -   b) at least one compound of the above-specified formula (II)    -   in which    -   R⁶ is hydrogen.

Particular preference is given to metal azo pigments comprising theadducts of

-   -   a) at least three metal azo compounds which differ at least in        the type of metal and which each contain structural units of the        above-specified formula (I)        -   in which R¹ and R² are OH,        -   and        -   R³ and R⁴ are ═O        -   and        -   Ni²⁺ and/or Zn²⁺ ions and at least one further metal ion Me,        -   where        -   Me is a di- or trivalent metal ion selected from the group            of Cu²⁺, Al³⁺, Fe²⁺, Fe³⁺, Co²⁺ and Co³⁺,        -   with the proviso that the amount of Zn²⁺ and Ni²⁺ ions            together is 70 to 95 mol % and the amount of metal ions Me            is 5 to 30 mol %,        -   the amount of Zn²⁺ and Ni²⁺ ions together preferably being            70 mol % to less than 95 mol % and the amount of metal ions            Me being more than 5 mol % to 30 mol %, the amount of Zn²⁺            and Ni²⁺ ions together more preferably being 70 to 94 mol %            and the amount of metal ions Me being 6 to 30 mol %, the            amount of Zn²⁺ and Ni²⁺ ions together preferably being 75 to            90 mol % and the amount of metal ions Me being 10 to 25 mol            %, and the amount of Zn²⁺ and Ni²⁺ ions together especially            being 80 to 85 mol % and the amount of metal ions Me being            15 to 20 mol %, based in each case on one mole of all metal            ions in the metal azo pigment,        -   and        -   where the molar ratio of Zn²⁺ to Ni²⁺ ions in the metal azo            pigment is 92:5 to 5:92, preferably 70:10 to 10:70 and more            preferably 60:25 to 25:60,        -   and    -   b) at least one compound of the above-specified formula (II)        -   in which        -   R⁶ is hydrogen.

Compounds suitable for forming an adduct in the sense of the abovedefinition with the metal azo compounds of component a) may be eitherorganic or inorganic compounds. These compounds are referred tohereinafter as adduct formers.

Adduct formers suitable in principle come from an extremely wide varietyof different compound classes. For purely practical reasons, preferenceis given to those compounds which are solid or liquid under standardconditions (25° C., 1 bar).

Among the liquid substances, preference is generally given to thosehaving a boiling point of 100° C. or higher, preferably of greater thanor equal to 150° C. at 1 bar. Suitable adduct formers are generallyacyclic and cyclic organic compounds, for example aliphatic and aromatichydrocarbons which may be substituted, for example, by OH, COOH, NH₂,substituted NH₂, CONH₂, substituted CONH₂, SO₂NH₂, substituted SO₂NH₂,SO₃H, halogen, NO₂, CN, —SO₂-alkyl, —SO₂-aryl, —O-alkyl, —O-aryl,—O-acyl.

Carboxamides and sulphonamides are a preferred group of adduct formers;also especially suitable are urea and substituted ureas such asphenylurea, dodecylurea and others, and the polycondensates thereof withaldehydes, especially formaldehyde; heterocycles such as barbituricacid, benzimidazolone, benzimidazolone-5-sulphonic acid,2,3-dihydroxyquinoxaline, 2,3-dihydroxyquinoxaline-6-sulphonic acid,carbazole, carbazole-3,6-disulphonic acid, 2-hydroxyquinoline,2,4-dihydroxyquinoline, caprolactam, melamine,6-phenyl-1,3,5-triazine-2,4-diamine,6-methyl-1,3,5-triazine-2,4-diamine, cyanuric acid.

Likewise suitable in principle as adduct formers are polymers,preferably water-soluble polymers, for example ethylene-propylene oxideblock polymers, preferably having an M_(n) greater than or equal to1000, especially from 1000 to 10 000 g/mol, polyvinyl alcohol,poly(meth)acrylic acids, modified cellulose such as carboxymethylcelluloses, hydroxyethyl and -propyl celluloses, methyl and ethylhydroxyethyl celluloses.

According to the invention, the adduct formers used are those of theformula (II). Especially preferred here is melamine.

In general, the metal azo pigments of the invention contain 0.05 to 4mol, preferably 0.5 to 2.5 mol and most preferably 1.0 to 2.0 mol ofcompounds of the formula (II) per mole of structural units of theformula (I).

The metal azo pigments of the invention preferably have a specificsurface area (m²/g) of 50 to 200 m²/g, especially 80 to 160 m²/g, mostpreferably 100 to 150 m²/g. The surface area is determined in accordancewith DIN 66131: determination of the specific surface area of solids bygas adsorption according to Brunauer, Emmett and Teller (B.E.T).

The metal azo pigments of the invention may be physical mixtures orchemical mixed compounds.

Preferably, the physical mixtures are mixtures of adducts of said metalazo compounds of component a) and the compounds of the formula (II) ofcomponent b) which differ at least in terms of the type of metals.Preferred examples are the physical mixture of the adducts of a1) thepure NI azo compound with b1) melamine and the adducts of a2) the pureZn azo compound with b2) melamine and the adducts of a3) with at leastone further Me azo compound with b3) melamine.

The chemical mixed compounds are, for example and with preference,adducts of metal azo compounds of component a) with compounds of theformula (II) of component b), preferably melamine, where the Zn²⁺ andNi²⁺ ions, and any further metal ion Me, are incorporated into a commoncrystal lattice.

The metal azo pigments of the invention can be prepared by reactingalkali metal salts of the formula (III), or tautomers thereof,preferably the sodium or potassium salts, in the presence of at leastone compound of the formula (II) with nickel and zinc salts and one ormore metal salts from the group of the di- or trivalent iron, cobalt,aluminium and copper salts. The metal azo pigments of the invention canalso be prepared by mixing the adducts of a1) metal azo compoundscontaining structural units of the formula (I) and Ni²⁺ ions and b1)compounds of the formula (II) with adducts of a2) metal azo compoundscontaining structural units of the formula (I) and Zn²⁺ ions and b2)compounds of formula (II) with adducts of a3) metal azo compoundscontaining structural units of the formula (I) and metal ions Me and b3)compounds of the formula (II).

The present invention further provides a process for producing the metalazo pigments of the invention, which is characterized in that at leastone compound of the formula (III), or tautomers thereof,

-   -   in which    -   X is an alkali metal on, preferably a sodium or potassium ion,    -   R¹ and R² are each independently OH, NH₂ or NHR⁵,    -   R³ and R⁴ are each independently ═O or ═NR⁵,    -   and    -   R⁵ is hydrogen or alkyl, preferably C₁-C₄-alkyl,        in the presence of at least one compound of the formula (II), is        reacted simultaneously or successively with at least one nickel        salt and at least one zinc salt and with at least one further        metal salt from the group of the Cu²⁺, Al³⁺, Fe²⁺, Fe³⁺, Co²⁺        and Co³⁺ salts, where 0.05 to 0.9 mol of at least one nickel        salt, 0.05 to 0.9 mol of at least one zinc salt and 0.05 to 0.3        mol, preferably more than 0.05 mol to 0.3 mol, more preferably        0.06 to 0.3 mol and most preferably 0.1 to 0.3 mol of at least        one further metal salt from the abovementioned group of the        metal salts are used per mole of compound of the formula (III),        and the sum total of the molar amounts of all these metal salts        together is one mole.

Preferably, 0.1 to 0.8 mol of at least one nickel salt and 0.1 to 0.8mol of at least one zinc salt and 0.1 to 0.25 mol of at least onefurther metal salt from the abovementioned group are used per mole ofcompound of the formula (III).

Most preferably, 0.25 to 0.6 mol of at least one nickel salt and 0.25 to0.6 mol of at least one zinc salt and 0.15 to 0.2 mol of at least onefurther metal salt from the abovementioned group are used per mole ofcompound of the formula (III).

In general, the process of the invention is performed using 0.05 to 4mol, preferably 0.5 to 2.5 mol and most preferably 1.0 to 2.0 mol ofcompound of the formula (II) per mole of compound of the formula (III).

Alternatively, for the preparation, instead of the di-alkali metalcompound of the formula (III), it is also possible to use a mono-alkalimetal compound of the formula (IIIa), or tautomers thereof,

-   -   in which X, R¹, R², R³ and R⁴ have the definition given for        formula (III),        or a mixture of compounds of the formula (III) and (IIIa). The        stated molar amounts of nickel and zinc salts and the further        metal salts from the abovementioned group and of compounds of        the formula (II) in these cases relate to the sum total of the        molar amounts of the compounds (III) and (IIIa) used.

The process of the invention is generally conducted at a temperature of60 to 95° C. in aqueous solution at a pH below 7. The nickel and zincsalts for use in accordance with the invention and the further metalsalts from the abovementioned group can be used individually or as amixture with one another, preferably in the form of an aqueous solution.The compounds of the formula (II) may likewise be added individually oras a mixture with one another, preferably in the form of the solids.

In general, the process of the invention is conducted in such a way thatthe azo compound of the formula (III), preferably as the sodium orpotassium salt, is initially charged, one or more compounds of theformula (II), preferably melamine, is/are added and then reaction iseffected successively or simultaneously with at least one nickel saltand at least one zinc salt and one or more metal salts from theabove-specified group, preferably in the form of the aqueous solutionsof these salts, preferably at pH values less than 7. Suitable substancesfor adjusting the pH are sodium hydroxide solution, potassium hydroxidesolution, sodium carbonate, sodium hydrogencarbonate, potassiumcarbonate and potassium hydrogencarbonate.

Useful nickel and zinc salts preferably include the water-soluble saltsthereof, especially chlorides, bromides, acetates, formates, nitrates,sulphates, etc. Nickel and zinc salts used with preference have a watersolubility of more than 20 g/l, especially more than 50 g/l, at 20° C.

Useful further metal salts from the group of the di- or trivalent iron,cobalt, aluminium and copper salts preferably include the water-solublesalts thereof, especially the chlorides, bromides, acetates, nitratesand sulphates thereof, preferably the chlorides thereof.

The metal azo pigments of the invention obtained in this way can then beisolated by filtration of the aqueous suspensions thereof as an aqueousfiltercake. This filtercake, optionally after washing with hot water,can be dried by means of standard drying methods.

Useful drying methods include, for example, paddle drying or spraydrying of corresponding aqueous slurries.

Subsequently, the pigment can be reground.

If the metal azo pigments of the invention have excessively hard grainsor are too hard to be dispersed for the desired application, they can beconverted to soft-grained pigments, for example by the method describedin DE-A 19 847 586.

The present invention further provides a process for producing the metalazo pigments of the invention, which is characterized in that

-   -   (i) at least one adduct of        -   a1) a metal azo compound containing structural units of the            above-specified formula (I)        -   in which        -   R¹, R², R³, R⁴ and R⁵ have the above-specified general and            preferred definition,        -   and        -   Zn²⁺ ions,        -   and        -   b1) at least one compound of the above-specified            formula (II) in which R⁶ has the general and preferred            definitions given above,        -   and the amount of Zn²⁺ metal ions is 100 mol %, based on one            mole of all metal ions in the adduct a1)/b1),            with    -   (ii) at least one adduct of        -   a2) a metal azo compound containing structural units of the            above-specified formula (I)        -   in which        -   R¹, R², R³, R⁴ and R⁵ have the above-specified general and            preferred definition,        -   and    -   Ni²⁺ ions,    -   and    -   b2) at least one compound of the above-specified formula (II) in        which R⁶ has the general and preferred definitions given above,    -   and the amount of Ni²⁺ metal ions is 100 mol %, based on one        mole of all metal ions in the adduct a2)/b2),    -   and    -   a3) a metal azo compound containing structural units of the        above-specified formula (I)    -   in which    -   R¹, R², R³, R⁴ and R⁵ have the above-specified general and        preferred definition,    -   and    -   at least one metal ion Me,    -   where    -   Me is a di- or trivalent metal ion selected from the group of        Cu²⁺, Al³⁺, Fe²⁺, Fe³⁺, Co²⁺ and Co³⁺,    -   and    -   b3) at least one compound of the above-specified formula (II) in        which R⁶ has the general and preferred definitions given above,        -   and the amount of Me metal ions is 100 mol %, based on one            mole of all metal ions in the adduct a3)/b3),            are mixed with one another, where 0.05 to 19 mol of adduct            a2)/b2) are used and 0.05 to 0.3 mol, preferably more than            0.05 mol to 0.3 mol, more preferably 0.06 to 0.3 mol and            most preferably 0.1 to 0.3 mol of adduct a3)/b3) are used            per mole of adduct a1)/b1), based on the sum total of the            molar amount of adducts a1)/b1) and a2)/b2).

The metal azo pigments of the invention are notable for particularlygood dispersibility and a high colour intensity. Chroma and transparencyhave excellent adjustability.

The metal azo pigments of the invention are of excellent suitability forall pigment applications, especially also in the form of the pigmentpreparations thereof.

The present invention further provides pigment preparations comprisingat least one metal azo pigment of the invention and at least oneauxiliary and/or additive.

Useful auxiliaries or additives generally include all additions that arecustomary for pigment preparations, for example those from the group ofthe surface-active agents such as dispersants, surfactants, wettingagents, emulsifiers, and those from the group of the surface-coveringagents, bases and solvents. In principle, the auxiliary or additive isguided by the nature of the target system. If the target system is, forexample, a lacquer or a printing ink, the auxiliary or additive is thenselected so as to achieve maximum compatibility with the target system.

Preferably, the pigment preparations of the invention comprise at leastone surface-active agent.

Surface-active agents in the context of the present invention areespecially understood to mean dispersants, which stabilize the pigmentparticles in their fine particulate form in aqueous media. “Fineparticulate” is preferably understood to mean a fine distribution of0.001 to 5 μm, especially of 0.005 to 1 μm, more preferably of 0.005 to0.5 μm. The pigment preparation of the invention is preferably in fineparticulate form.

Suitable surface-active agents are, for example, anionic, cationic,amphoteric or nonionic in nature.

Suitable anionic surface-active agents (c) are especially condensationproducts of aromatic sulphonic acids with formaldehyde, such ascondensation products of formaldehyde and alkylnaphthalenesulphonicacids or of formaldehyde, naphthalenesulphonic acids and/orbenzenesulphonic acids, condensation products of optionally substitutedphenol with formaldehyde and sodium bisulphite. Also suitable aresurface-active agents from the group of the sulphosuccinic esters andalkybenzenesulphonates. Also ionically modified, especially sulphated orcarboxylated, alkoxylated fatty acid alcohols or salts thereof.Alkoxylated fatty acid alcohols are especially understood to mean thoseC₆-C₂₂ alcohols endowed with 5 to 120, preferably 5 to 60 and especiallywith 5 to 30 ethylene oxide, which are saturated or unsaturated.Additionally useful are lignosulphonates in particular, for examplethose which are obtained by the sulphite or Kraft process. They arepreferably products which are partially hydrolysed, oxidized,propoxylated, sulphonated, sulphomethylated or desulphonated and whichare fractionated by known methods, for example according to themolecular weight or the degree of sulphonation. Mixtures of sulphite andKraft lignosulphonates are also very effective. Especially suitable arelignosulphonates with an average molecular weight between 1000 and 100000 g/mol, a content of active lignosulphonate of at least 80% by weightand, preferably, a low content of polyvalent cations. The degree ofsulphonation can be varied within wide limits.

Examples of useful nonionic surface-active agents include: reactionproducts of alkylene oxides with compounds capable of being alkylated,such as, for example, fatty alcohols, fatty amines, fatty acids,phenols, alkylphenols, arylalkylphenols, such as styrene-phenolcondensates, carboxamides and resin acids. These are, for example,ethylene oxide adducts from the class of the reaction products ofethylene oxide with:

1) saturated and/or unsaturated fatty alcohols having 6 to 22 carbonatoms or2) alkylphenols having 4 to 12 carbon atoms in the alkyl radical or3) saturated and/or unsaturated fatty amines having 14 to 20 carbonatoms or4) saturated and/or unsaturated fatty acids having 14 to 20 carbon atomsor5) hydrogenated and/or unhydrogenated resin adds.

Useful ethylene oxide adducts especially include the alkylatablecompounds mentioned in 1) to 5) having 5 to 120, especially 5 to 100,especially 5 to 60 and more preferably 5 to 30 mol of ethylene oxide.

Suitable surface-active agents are likewise the esters of thealkoxylation product of the formula (X) that are known from DE-A 19 712486 or from DE-A 19 535 246, which correspond to the formula (XI), andthe latter optionally in a mixture with the parent compounds of theformula (X). The alkoxylation product of a styrene-phenol condensate ofthe formula (X) is as defined below:

in which

-   R¹⁵ is hydrogen or C₁-C₄-alkyl,-   R¹⁶ is hydrogen or CH₃.-   R¹⁷ is hydrogen, C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkoxycarbonyl or    phenyl,-   m is a number from 1 to 4,-   n is a number from 6 to 120,-   R¹⁸ is the same or different for every unit indicated by n and is    hydrogen, CH₃ or phenyl, where, in the case that CH₃ is present in    some of the different —(—CH₂—CH(R¹⁸)—O—) groups, R¹⁸ is CH₃ in 0% to    60% of the total value of n and R¹⁸ is hydrogen in 100% to 40% of    the total value of n, and where, in the case that phenyl is present    in some of the different —(—CH₃—CH(R¹⁸)—O—) groups, R¹⁸ is phenyl in    0% to 40% of the total value of n and R¹⁸ is hydrogen in 100% to 60%    of the total value of n.

The esters of the alkoxylation products (X) correspond to the formula(XI)

in which

-   R^(15′), R^(16′), R^(17′), R^(18′), m′ and n′ assume the scope of    the definition of R¹⁵, R¹⁶, R¹⁷, R¹⁸, m and n, but independently    thereof,-   X is the —SO₃, —SO₂, —PO₃ or —CO—(R¹⁹)—COO group,-   Kat is a cation from the group of H, Li, Na, K, NH₄ or HO—CH₂CH₂NH₃,    where two Kat are present in the case that X=—PO₃, and-   R¹⁹ is a divalent aliphatic or aromatic radical, preferably    C₁-C₄-alkylene, especially ethylene, C₂-C₄ monounsaturated radicals,    especially acetylene or optionally substituted phenylene, especially    ortho-phenylene, where possible substituents preferably include    C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkoxycarbonyl or phenyl.

A preferred surface-active agent used is the compound of the formula(XI). Preferably a compound of the formula (XI) in which X is a radicalof the formula —CO—(R¹⁹)—COO⁻ and R¹⁹ is as defined above.

Preference is likewise given to using, as surface-active agent, acompound of the formula (XI) together with a compound of the formula(X). Preferably, the surface-active agent in this case contains 5% to99% by weight of the compound (XI) and 1% to 95% by weight of thecompound (X).

The surface-active agent of component (c) is preferably used in thepigment preparation in an amount of 0.1% to 100% by weight, especially0.5% to 60% by weight, based on the metal azo pigment of the inventionused.

It will be appreciated that the pigment preparation of the invention mayalso contain further additions. For example, additions which lower theviscosity of an aqueous suspension and/or increase the solids content,for example carboxamides and sulphonamides, may be added in an amount ofup to 10% by weight, based on the pigment preparation.

Further additions are, for example, inorganic and organic bases, andadditions customary for pigment preparations.

Bases include: alkali metal hydroxides, for example NaOH, KOH or organicamines such as alkylamines, especially alkanolamines oralkylalkanolamines.

Particularly preferred examples include methylamine, dimethylamine,trimethylamine, ethanolamine, n-propanolamine, n-butanolamine,diethanolamine, triethanolamine, methylethanolamine ordimethylethanolamine.

Examples of suitable carboxamides and sulphonamides include: urea andsubstituted ureas such as phenylurea, dodecylurea and others;heterocycles such as barbituric acid, benzimidazolone,benzimidazolone-5-sulphonic acid, 2,3-dihydroxyquinoxaline,2,3-dihydroxyquinoxaline-6-sulphonic acid, carbazole,carbazole-3,6-disulphonic acid, 2-hydroxyquinoline,2,4-dihydroxyquinoline, caprolactam, melamine,6-phenyl-1,3,5-triazine-2,4-diamine,6-methyl-1,3,5-triazine-2,4-diamine, cyanuric acid.

The base is optionally present up to an amount of 20% by weight,preferably up to 10% by weight, based on the pigment.

In addition, the pigment preparations of the invention may still containinorganic and/or organic salts as a result of the preparation.

The pigment preparations of the Invention are preferably solid at roomtemperature. More particularly, the pigment preparations of theinvention are in the form of powders or granules.

The pigment preparations of the invention are of excellent suitabilityfor all pigment applications.

The present invention further provides for the use of at least one metalazo pigment of the invention or of a pigment preparation of theinvention for pigmentation of all kinds of lacquers for the productionof printing inks, distempers or emulsion paints, for the bulk colouringof paper, for the bulk colouring of synthetic, semisynthetic or naturalmacromolecular substances, for example polyvinyl chloride, polystyrene,polyamide, polyethylene or polypropylene. They can also be used for thespin dyeing of natural, regenerated or synthetic fibres, for examplecellulose, polyester, polycarbonate, polyacrylonitrile or polyamidefibres, and for printing of textiles and paper. These pigments can beused to produce finely divided, stable, aqueous pigmentations foremulsion paints and other paints usable for paper colouring, for thepigment printing of textiles, for laminate printing or for the spindyeing of viscose, by grinding or kneading in the presence of nonionic,anionic or cationic surfactants.

The metal azo pigments of the invention are additionally of excellentsuitability for inkjet applications and for colour filters forliquid-crystal displays.

In a likewise preferred embodiment, the pigment preparations of theinvention comprise at least one organic compound (d) selected from thegroup of the terpenes, terpenoids, fatty acids, fatty acid esters andthe homo- or copolymers, such as random or block copolymers having asolubility in pH-neutral water at 20° C. of less than 1 g/l, especiallyless than 0.1 g/l. The organic compound (d) is preferably solid orliquid at room temperature (20° C.) under standard atmosphere and, if itis liquid, has a boiling point of preferably >100° C., especially >150°C.

Preferred polymers have both a hydrophilic and a hydrophobic, preferablypolymeric, molecular moiety. Examples of such polymers are randomcopolymers based on fatty acids or long-chain C₁₂-C₂₂ hydrocarbons andpolyalkylene glycols, especially polyethylene glycol. Also blockcopolymers based on (poly)hydroxy fatty acids and polyalkylene glycol,especially polyethylene glycol, and also graft copolymers based onpoly(meth)acrylate and polyalkylene glycol, especially polyethyleneglycol.

Preferred compounds from the group of the terpenes, terpenoids, fattyacids and fatty acid esters include: ocimene, myrcene, geraniol, nerol,linalool, citronellol, geranial, citronellal, neral, limonene, menthol,for example (−)-menthol, menthone or bicyclic monoterpenes, saturatedand unsaturated fatty acids having 6 to 22 carbon atoms, for exampleoleic acid, linoleic acid and linolenic acid or mixtures thereof.

Also useful as organic compounds of component (d) are the abovementionedadduct formers, provided that they obey the criteria desired for thecompound of component (d).

Particularly preferred pigment preparations comprise:

-   50%-99% by weight of at least one metal azo pigment of the invention    and-   1%-50% by weight, preferably 2% to 50% by weight of at least one    compound of component (d).

Optionally, the pigment preparation of the invention additionallycomprises a surface-active agent (c).

More preferably, the preparations of the invention consist to an extentof more than 90% by weight, preferably more than 95% by weight andespecially more than 97% by weight of at least one metal azo pigment ofthe invention, at least one organic compound of component (d) andoptionally at least one surface-active agent of component (c) andoptionally at least one base.

The pigment preparations of the Invention in this composition areespecially suitable for pigmentation of inkjet inks and colour filtersfor liquid-crystal displays.

The present invention further provides a process for producing thepigment preparations of the invention, which is characterized in that atleast one metal azo pigment of the invention and at least one auxiliaryor additive, especially at least one organic compound of component (d)and optionally at least one surface-active agent of component (c) andoptionally at least one base are mixed with one another.

The present invention likewise provides for the use of the metal azopigments of the invention or of the pigment preparations of theinvention for production of colour filters for liquid-crystal displays.This use will be described hereinafter using the example of the pigmentdispersion method according to the photoresist process.

The inventive use of the pigment preparations of the invention forproduction of colour filters is characterized in that, for example, atleast one metal azo pigment of the invention or a pigment preparation ofthe invention, especially a solid pigment preparation, is homogenized,optionally with a binder resin and an organic solvent, optionally withaddition of a dispersant, and then wet-comminuted continuously orbatchwise to a particle size by number (electron microscopydetermination) of 99.5%<1000 nm, preferably 95%<500 nm and especially90%<200 nm.

Useful wet comminution methods include, for example, stirrer ordissolver dispersion, grinding by means of stirred ball mills or beadmills, kneaders, roll mils, high-pressure homogenization or ultrasounddispersion.

During the dispersion treatment or thereafter, at least one photocurablemonomer and a photoinitiator are added. After the dispersion, it ispossible to introduce further binder resin, solvent, or admixturescustomary for photoresists, as required for the desired photosensitivecoating formulation (photoresist) for production of the colour filters.In the context of this invention, a photoresist is understood to mean apreparation comprising at least one photocurable monomer and aphotoinitiator.

The present invention also provides a process for producing colourfilters for liquid-crystal displays, which is characterized in that atleast one metal azo pigment of the invention or a pigment preparation ofthe invention is homogenized, optionally with a binder resin and anorganic solvent, optionally with addition of a dispersant, and thenwet-comminuted continuously or batchwise to a particle size by number(electron microscopy determination) of 99.5%<1000 nm and, during thedispersion treatment or thereafter, at least one photocurable monomerand a photoinitiator are added.

Useful possible dispersants include dispersants which are suitable forthis application and are generally commercially available, for examplepolymeric, ionic or nonionic dispersants, for example based onpolycarboxylic acids or polysulphonic acids, and also polyethyleneoxide-polypropylene oxide block copolymers. In addition, it is alsopossible to use derivatives of organic dyes as dispersants orco-dispersants.

The production of colour filters therefore gives rise to “formulations”comprising, based on the formulation:

-   -   at least one metal azo pigment of the invention,    -   optionally a binder resin,    -   at least one organic solvent and    -   optionally a dispersant.

In a preferred embodiment, the formulation contains (figures based onformulation):

-   1%-50% by weight of a metal azo pigment of the invention-   0%-20% by weight of binder resin-   0%-20% by weight of dispersant-   10%-94% by weight of organic solvent.

The coating of the photoresist onto a plate to produce the colouredimage element patterns can be accomplished either by direct or indirectapplication. Examples of application methods include: roller coating,spin coating, spray coating, dip coating and air-knife coating.

Useful plates include, according to the application, for example:transparent glasses such as white or blue glass plates, silicate-coatedblue glass plate, synthetic resin plate or films based, for example, onpolyester resin, polycarbonate resin, acrylic resin or vinyl chlorideresin, and also metal plates based on aluminium, copper, nickel orsteel, and ceramic plates or semiconductor plates having appliedphotoelectric transfer elements.

The application is generally effected such that the layer thickness ofthe photosensitive layer obtained is 0.1 to 10 μm.

The application may be followed by thermal drying of the layer.

The exposure is preferably effected by exposing the photosensitive layerto an active light beam, preferably in the form of an image pattern bymeans of a photomask. This results in curing of the layer at the exposedsites. Suitable light sources are, for example: high-pressure andultrahigh-pressure mercury vapour lamp, xenon lamp, metal halide lamp,fluorescent lamp, and laser beam in the visible region.

-   -   The development which follows the exposure removes the unexposed        portion of the coating and gives the desired image pattern form        of the colour elements. Standard development methods include        spraying with or dipping into aqueous alkaline developer        solution or into an organic solvent comprising inorganic alkali,        for example sodium hydroxide or potassium hydroxide, sodium        metasilicate or organic bases such as monoethanolamine,        diethanolamine, triethanolamine, triethylamine or salts thereof.

The development is generally followed by a thermal post-drying/curing ofthe image patterns. The inventive use of the metal azo pigments ispreferably characterized in that they are used alone or in a mixturewith other pigments that are customary for the production of colourfilters in the colour filters or pigment preparations or formulationsfor colour filters.

These “other pigments” may either be other metal salts of an azocompound of the formula (I) or pigment preparations based thereon orother inorganic or organic pigments.

With regard to the selection of any other pigments to be used as well,there is no restriction in accordance with the invention. Both inorganicand organic pigments are useful.

Preferred organic pigments are, for example, those of the monoazo,disazo, laked azo, β-naphthol, naphthol AS, benzimidazolone, disazocondensations, azo metal complex, isoindoline and isoindolinone series,and also polycyclic pigments, for example from the phthalocyanine,quinacridone, perylene, perinone, thioindigo, anthraquinone, dioxazine,quinophthalone and diketopyrrolopyrrole series. Also laked dyes such asCa, Mg and Al lakes of sulpho- or carboxyl-containing dyes.

Examples of other organic pigments which can optionally be used inaddition are:

-   Colour Index Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93,    94, 109, 110, 117, 125, 137, 138, 139, 147, 148, 150, 153, 154, 166,    173, 185, or-   Colour Index Pigment Orange 13, 31, 36, 38, 40, 42, 43, 51, 55, 59,    61, 64, 65, 71, 72, 73 or-   Colour Index Pigment Red 9, 97, 122, 123, 144, 149, 166, 168, 177,    180, 192, 215, 216, 224, 254, 272, or-   Colour Index Pigment Green 7, 10, 36, 37, 45, 58 or-   Colour Index Pigment Blue 15, 15:1, 15-2, 15:3, 15:4, 15:6, 16 and-   Colour Index Pigment Violet 19, 23.

In addition, it is also possible to use soluble organic dyes inconjunction with the novel pigments of the invention.

If “other pigments” are used in addition, the proportion of metal azopigment of the invention is preferably 1%-99% by weight, especially20%-80% by weight, based on the total amount of all pigments used.Particular preference is given to the pigment preparations of theinvention and to formulations comprising at least one metal azo pigmentof the invention and C.I. Pigment Green 36 and/or C.I. Pigment Green 58in a ratio of 20% to 80% by weight of metal azo pigment to 80% to 20% byweight of C.I. Pigment Green 36 and/or C.I. Pigment Green 58, preferablyof 40% to 60% by weight to 60% to 40% by weight.

There is no particular restriction in accordance with the invention withregard to the binder resins which can be used together with the“pigment” or pigment preparations based thereon in colour filters or inthe formulations for production of colour filters, for example by thepigment dispersion method, and useful binder resins are especially thefilm-forming resins known per se for use in colour filters.

For example, useful binder resins include those from the group of thecellulose resins such as carboxymethyl hydroxyethyl cellulose andhydroxyethyl cellulose, acrylic resins, alkyd resins, melamine resins,epoxy resins, polyvinyl alcohols, polyvinylpyrrolidones, polyamides,polyamide imines, polyimides, polyimide precursors such as those of theformula (14), disclosed in JP-A 11 217 514, and the esterificationproducts thereof.

Examples of these include reaction products of tetracarboxylicdianhydride with diamines.

Useful binder resins also include those which contain photopolymerizableunsaturated bonds. The binder resins may, for example, be those formedfrom the group of acrylic resins. Particular mention should be made hereof homo- and copolymers of polymerizable monomers, for example methyl(meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl(meth)acrylate, styrene and styrene derivatives, and also copolymersbetween carboxyl-bearing polymerizable monomers such as (meth)acrylicacid, itaconic acid, maleic acid, maleic anhydride, monoalkyl maleates,especially with alkyl having 1 to 12 carbon atoms, and polymerizablemonomers such as (meth)acrylic acid, styrene and styrene derivatives,for example α-methylstyrene, m- or p-methoxystyrene, p-hydroxystyrene.Examples include reaction products of carboxyl-containing polymericcompounds with compounds each containing an oxirane ring and anethylenically unsaturated bond, for example glycidyl (meth)acrylate,acryloyl glycidyl ether and itaconic acid monoalkyl glycidyl ether,etc., and also reaction products of carboxyl-containing polymericcompounds with compounds each containing a hydroxyl group and anethylenically unsaturated bond (unsaturated alcohols), such as allylalcohol, 2-buten-4-ol, oleyl alcohol, 2-hydroxyethyl (meth)acrylate,N-methylolacrylamide, etc.;

In addition, such binder resins may also contain unsaturated compoundshaving free isocyanate groups.

In general, the equivalents of unsaturation (molar mass of binder resinper unsaturated compound) of the binder resins mentioned are 200 to3000, especially 230 to 1000, in order to achieve both sufficientphotopolymerizability and hardness of the film. The acid value isgenerally 20 to 300, especially 40 to 200, in order to achievesufficient alkali development capacity after the exposure of the film.

The mean molar mass of the binder resins for use is between 1500 and 200000 and is especially 10 000 to 50 000 g/mol.

The organic solvents used in the inventive use of the pigmentpreparations for colour filters are, for example, ketones, alkyleneglycol ethers, alcohols and aromatic compounds. Examples from the groupof the ketones are: acetone, methyl ethyl ketone, cyclohexanone, etc.;from the group of the alkylene glycol ethers: Methyl Cellosolve(ethylene glycol monomethyl ether), Butyl Cellosolve (ethylene glycolmonobutyl ether), Methyl Cellosolve Acetate, Ethyl Cellosolve Acetate,Butyl Cellosolve Acetate, ethylene glycol monopropyl ether, ethyleneglycol monohexyl ether, ethylene glycol dimethyl ether, diethyleneglycol ethyl ether, diethylene glycol diethyl ether, propylene glycolmonomethyl ether, propylene glycol monoethyl ether, propylene glycolmonopropyl ether, propylene glycol monobutyl ether, propylene glycolmonomethyl ether acetate, diethylene glycol methyl ether acetate,diethylene glycol ethyl ether acetate, diethylene glycol propyl etheracetate, diethylene glycol isopropyl ether acetate, diethylene glycolbutyl ether acetate, diethylene glycol t-butyl ether acetate,triethylene glycol methyl ether acetate, triethylene glycol ethyl etheracetate, triethylene glycol propyl ether acetate, triethylene glycolisopropyl ether acetate, triethylene glycol butyl ether acetate,triethylene glycol t-butyl ether acetate, etc.; from the group of thealcohols: methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butylalcohol, 3-methyl-3-methoxybutanol, etc.; from the group of the aromaticsolvents: benzene, toluene, xylene, N-methyl-2-pyrrolidone, ethylN-hydroxymethyl-2-acetate, etc.

Further other solvents are propane-1,2-diol diacetate,3-methyl-3-methoxybutyl acetate, ethyl acetate, tetrahydrofuran, etc.The solvents may be used individually or in mixtures with one another.

The invention further relates to a photoresist comprising at least onemetal azo pigment of the invention or at least one pigment preparationof the invention and at least one photocurable monomer and at least onephotoinitiator.

The photocurable monomers contain at least one reactive double bond andoptionally other reactive groups in the molecule.

Photocurable monomers are understood in this connection especially tomean reactive solvents or what are called reactive diluents, for examplefrom the group of the mono-, dl-, tri- and multifunctional acrylates andmethacrylates, vinyl ethers and glycidyl ethers. Useful reactive groupsadditionally present include allyl, hydroxyl, phosphate, urethane,secondary amine and N-alkoxymethyl groups.

Monomers of this kind are known to those skilled in the art and aredetailed, for example, in [Römpp Lexikon, Lacke und Druckfarben, Dr.Ulrich Zorll, Thieme Verlag Stuttgart-New York, 1998, p. 491/492].

The selection of monomers is guided especially by the nature andintensity of the radiation type used for the exposure, the desiredreaction with the photoinitiator and the film properties. It is alsopossible to use combinations of monomers.

Photoreaction initiators or photoinitiators are understood to meancompounds which form reactive intermediates as a result of theabsorption of visible or ultraviolet radiation, which can trigger apolymerization reaction, for example of the abovementioned monomersand/or binder resins. Photoreaction initiators are likewise commonlyknown and can likewise be found in [Römpp Lexikon, Lacke undDruckfarben, Dr. Ulrich Zorll, Thieme Verlag Stuttgart-New York, 1998,p. 445/446].

According to the invention, there is no restriction with regard to thephotocurable monomers or photoinitiators to be used.

The invention preferably relates to photoresists comprising

-   A) at least one metal azo pigment of the invention, especially in a    mixture with other pigments, preferably C.I. Pigment Green 36 and/or    Pigment Green 58 or a pigment preparation of the invention based    thereon,-   B1) at least one photocurable monomer,-   B2) at least one photoinitiator,-   C1) optionally an organic solvent,-   D) optionally a dispersant,-   E) optionally a binder resin,    and optionally further additions.

According to the invention, there is also no restriction with regard tothe methodology for production of the coloured image element patternsbased on the pigments or solid pigment preparations for use inaccordance with the invention. As well as the above-describedphotolithographic method, other methods such as offset printing,chemical etching or inkjet printing are likewise suitable. The selectionof the suitable binder resins and solvents and of pigment carrier mediaand further additions should be matched to the particular method. In theinkjet method, which is understood to mean both thermal and mechanicaland piezo-mechanical inkjet printing, useful carrier media for thepigments and any binder resins are not only purely organic but alsoaqueous-organic carrier media; aqueous-organic carrier media areactually preferred.

The examples which follow are intended to illustrate the presentinvention but without restricting it thereto.

EXAMPLES Preparation of the Azobarbituric Acid Precursor (Method 1)

154.1 g of diazobarbituric acid and 128.1 g of barbituric acid wereintroduced into 3600 g of distilled water at 85° C. Subsequently,aqueous potassium hydroxide solution was used to establish a pH of about5 and the mixture was then stirred for 90 minutes.

Example 1: Preparation of Pigment 1

5000 g of distilled water were added at 82° C. to an azobarbituric acidprepared according to Method 1. Thereafter, 252.2 g of melamine wereintroduced. Subsequently, a mixture of 0.70 mol of an about 30%nickel(II) chloride solution, 0.05 mol of an about 30% zinc(II) chloridesolution and 0.250 mol of an about 20% cobalt(II) chloride solution wasadded dropwise. After 3 hours at 82° C., KOH was used to establish a pHof about 5.5. This was followed by dilution at 90° C. with about 1000 gof distilled water. Subsequently, 113 g of 30% hydrochloric acid wereadded dropwise and the mixture was heat-treated at 90° C. for 12 hours.Thereafter, aqueous potassium hydroxide solution was used to establish apH of about 5. Subsequently, the pigment was isolated on a suctionfilter, washed and dried in a vacuum drying cabinet at 80° C., andground in a standard laboratory mill for about 2 minutes. (=Pigment 1)

Examples 2 to 100

For preparation of inventive pigments 2 to 48 and of noninventivepigments 40 to 100, the procedure in each case was analogous toExample 1. In each case, 5000 g of distilled water were added at 82° C.to an azobarbituric acid prepared according to Method 1 and then 252.2 gof melamine were introduced. Subsequently, rather than the mixture ofnickel (II) chloride solution and zinc(II) chloride solution of Example1, a metal salt solution as specified in the examples which follow wasadded dropwise in each case. The workup and isolation, drying andgrinding of the respective pigment in all examples were analogous to themethod specified in Example 1.

Example 2: Preparation of Pigment 2

A mixture of 0.50 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 3: Preparation of Pigment 3

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.45mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% cobalt(II) chloride solution was added dropwise. After 3 hours at82° C., the mixture was adjusted to a pH of about 5.5 using KOH.(Pigment 3)

Example 4: Preparation of Pigment 4

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.70mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% cobalt(II) chloride solution was added dropwise. After 3 hours at82° C., the mixture was adjusted to a pH of about 5.5 using KOH.

Example 5: Preparation of Pigment 5

A mixture of 0.70 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% iron(II) chloride solution was added dropwise.

Example 6: Preparation of Pigment 6

A mixture of 0.50 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% iron(II) chloride solution was added dropwise.

Example 7: Preparation of Pigment 7

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.45mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% iron(II) chloride solution was added dropwise.

Example 8: Preparation of Pigment 8

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.70mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% iron(II) chloride solution was added dropwise.

Example 9: Preparation of Pigment 9

A mixture of 0.70 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.166 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 10: Preparation of Pigment 10

A mixture of 0.50 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.166 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 11: Preparation of Pigment 11

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.45mol of an about 30% zinc(II) chloride solution and 0.166 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 12: Preparation of Pigment 12

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.70mol of an about 30% zinc(II) chloride solution and 0.166 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 13: Preparation of Pigment 13

A mixture of 0.70 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% copper(II) chloride solution was added dropwise.

Example 14: Preparation of Pigment 14

A mixture of 0.50 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% copper(II) chloride solution was added dropwise.

Example 15: Preparation of Pigment 15

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.45mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% copper(II) chloride solution was added dropwise.

Example 16: Preparation of Pigment 16

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.70mol of an about 30% zinc(II) chloride solution and 0.250 mol of an about20% copper(II) chloride solution was added dropwise.

Example 17: Preparation of Pigment 17

A mixture of 0.80 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 18: Preparation of Pigment 18

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 19: Preparation of Pigment 19

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.55mol of an about 30% zinc(II) chloride solution and 0.15 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 20: Preparation of Pigment 20

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.80mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 21: Preparation of Pigment 21

A mixture of 0.80 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% iron(II) chloride solution was added dropwise.

Example 22: Preparation of Pigment 22

A mixture of 0.80 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% iron(II) chloride solution was added dropwise.

Example 23: Preparation of Pigment 23

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.55mol of an about 30% zinc(II) chloride solution and 0.15 mol of an about20% iron(II) chloride solution was added dropwise.

Example 24: Preparation of Pigment 24

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.80mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% iron(II) chloride solution was added dropwise.

Example 25: Preparation of Pigment 25

A mixture of 0.80 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.10 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 26: Preparation of Pigment 26

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.10 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 27: Preparation of Pigment 27

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.55mol of an about 30% zinc(II) chloride solution and 0.10 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 28: Preparation of Pigment 28

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.80mol of an about 30% zinc(II) chloride solution and 0.10 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 29: Preparation of Pigment 29

A mixture of 0.80 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% copper(II) chloride solution was added dropwise.

Example 30: Preparation of Pigment 30

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% copper(III) chloride solution was added dropwise.

Example 31: Preparation of Pigment 31

A mixture of 0.30 mol of an about 30% nickel(II) chloride solution, 0.55mol of an about 30% zinc(II) chloride solution and 0.15 mol of an about20% copper(II) chloride solution was added dropwise.

Example 32: Preparation of Pigment 32

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.80mol of an about 30% zinc(II) chloride solution and 0.150 mol of an about20% copper(II) chloride solution was added dropwise.

Example 33: Preparation of Pigment 33

A mixture of 0.88 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 34: Preparation of Pigment 34

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 35: Preparation of Pigment 35

A mixture of 0.45 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 36: Preparation of Pigment 36

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.88mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 37: Preparation of Pigment 37

A mixture of 0.88 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% iron(II) chloride solution was added dropwise.

Example 38: Preparation of Pigment 38

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% iron(II) chloride solution was added dropwise.

Example 39: Preparation of Pigment 39

A mixture of 0.45 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% iron(II) chloride solution was added dropwise.

Example 40: Preparation of Pigment 40

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.88mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% iron(II) chloride solution was added dropwise.

Example 41: Preparation of Pigment 41

A mixture of 0.88 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.047 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 42: Preparation of Pigment 42

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.047 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 43: Preparation of Pigment 43

A mixture of 0.45 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.047 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 44: Preparation of Pigment 44

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.88mol of an about 30% zinc(II) chloride solution and 0.047 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 45: Preparation of Pigment 45

A mixture of 0.88 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 46: Preparation of Pigment 46

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 47: Preparation of Pigment 47

A mixture of 0.45 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 48: Preparation of Pigment 48

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.88mol of an about 30% zinc(II) chloride solution and 0.07 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 49: Preparation of Pigment 49

A mixture of 0.92 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 50: Preparation of Pigment 50

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 51: Preparation of Pigment 51

A mixture of 0.49 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 52: Preparation of Pigment 52

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.92mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 53: Preparation of Pigment 53

A mixture of 0.92 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% iron(II) chloride solution was added dropwise.

Example 54: Preparation of Pigment 54

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% iron(II) chloride solution was added dropwise.

Example 55: Preparation of Pigment 55

A mixture of 0.49 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% iron(II) chloride solution was added dropwise.

Example 56: Preparation of Pigment 56

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.92mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% iron(II) chloride solution was added dropwise.

Example 57: Preparation of Pigment 57

A mixture of 0.92 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.02 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 58: Preparation of Pigment 88

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.02 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 59. Preparation of Pigment 59

A mixture of 0.49 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.02 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 60: Preparation of Pigment 60

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.92mol of an about 30% zinc(II) chloride solution and 0.02 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 61: Preparation of Pigment 61

A mixture of 0.92 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% copper(II) chloride solution was added dropwise.

Example 62: Preparation of Pigment 62

A mixture of 0.65 mol of an about 30% nickel(II) chloride solution, 0.28mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% copper(II) chloride solution was added dropwise.

Example 63: Preparation of Pigment 63

A mixture of 0.49 mol of an about 30% nickel(II) chloride solution, 0.48mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% copper(II) chloride solution was added dropwise.

Example 64: Preparation of Pigment 64

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.92mol of an about 30% zinc(II) chloride solution and 0.03 mol of an about20% copper(II) chloride solution was added dropwise.

Example 65: Preparation of Pigment 65

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 66: Preparation of Pigment 66

A mixture of 0.40 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 67: Preparation of Pigment 67

A mixture of 0.25 mol of an about 30% nickel(II) chloride solution, 0.40mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 68: Preparation of Pigment 68

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.60mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 69: Preparation of Pigment 69

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% iron(II) chloride solution was added dropwise.

Example 70: Preparation of Pigment 70

A mixture of 0.40 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% iron(II) chloride solution was added dropwise.

Example 71: Preparation of Pigment 71

A mixture of 0.25 mol of an about 30% nickel(II) chloride solution, 0.40mol of an about 30% zinc(II) chloride solution and 0.35 mot of an about20% iron(II) chloride solution was added dropwise.

Example 72: Preparation of Pigment 72

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.60mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% iron(II) chloride solution was added dropwise.

Example 73: Preparation of Pigment 73

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.23 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 74: Preparation of Pigment 74

A mixture of 0.40 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.23 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 75: Preparation of Pigment 75

A mixture of 0.25 mol of an about 30% nickel(II) chloride solution, 0.40mol of an about 30% zinc(II) chloride solution and 0.23 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 76: Preparation of Pigment 76

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.60mol of an about 30% zinc(II) chloride solution and 0.23 mol of an about20% aluminium(III) chloride solution was added dropwise.

Example 77: Preparation of Pigment 77

A mixture of 0.60 mol of an about 30% nickel(II) chloride solution, 0.05mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 78: Preparation of Pigment 78

A mixture of 0.40 mol of an about 30% nickel(II) chloride solution, 0.25mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 79: Preparation of Pigment 79

A mixture of 0.25 mol of an about 30% nickel(II) chloride solution, 0.40mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 80: Preparation of Pigment 80

A mixture of 0.05 mol of an about 30% nickel(II) chloride solution, 0.60mol of an about 30% zinc(II) chloride solution and 0.35 mol of an about20% cobalt(II) chloride solution was added dropwise.

Example 81: Preparation of Pigment 81

A mixture of 0.933 mol of an about 30% nickel(II) chloride solution,0.067 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 82: Preparation of Pigment 82

$ A mixture of 0.667 mol of an about 30% nickel(II) chloride solutionand 0.333 mol of an about 30% zinc(II) chloride solution was addeddropwise.

Example 83: Preparation of Pigment 83

A mixture of 0.400 mol of an about 30% nickel(II) chloride solution and0.600 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 84: Preparation of Pigment 84

A mixture of 0.067 mol of an about 30% nickel(II) chloride solution and0.933 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 85: Preparation of Pigment 85

A mixture of 0.941 mol of an about 30% nickel(II) chloride solution and0.059 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 86: Preparation of Pigment 86

A mixture of 0.706 mol of an about 30% nickel(II) chloride solution and0.294 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 87: Preparation of Pigment 87

A mixture of 0.353 mol of an about 30% nickel(II) chloride solution and0.647 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 88: Preparation of Pigment 88

A mixture of 0.059 mol of an about 30% nickel(if) chloride solution and0.941 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 89: Preparation of Pigment 89

A mixture of 0.946 mol of an about 30% nickel(II) chloride solution and0.054 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 90: Preparation of Pigment 90

A mixture of 0.699 mol of an about 30% nickel(II) chloride solution and0.301 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 91: Preparation of Pigment 91

A mixture of 0.481 mol of an about 30% nickel(II) chloride solution and0.516 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 92: Preparation of Pigment 92

A mixture of 0.054 mol of an about 30% nickel(II) chloride solution and0.946 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 93: Preparation of Pigment 93

A mixture of 0.948 mol of an about 30% nickel(II) chloride solution and0.052 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 94: Preparation of Pigment 94

A mixture of 0.699 mol of an about 30% nickel(II) chloride solution and0.301 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 95: Preparation of Pigment 95

A mixture of 0.505 mol of an about 30% nickel(II) chloride solution and0.495 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 96: Preparation of Pigment 96

A mixture of 0.052 mol of an about 30% nickel(II) chloride solution and0.948 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 97: Preparation of Pigment 97

A mixture of 0.923 mol of an about 30% nickel(II) chloride solution and0.77 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 98: Preparation of Pigment 96

A mixture of 0.615 mol of an about 30% nickel(II) chloride solution and0.385 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 99: Preparation of Pigment 99

A mixture of 0.385 mol of an about 30% nickel(II) chloride solution and0.615 mol of an about 30% zinc(II) chloride solution was added dropwise.

Example 100: Preparation of Pigment 100

A mixture of 0.077 mol of an about 30% nickel(II) chloride solution and0.923 mol of an about 30% zinc(II) chloride solution was added dropwise.

Determination of Colour Strength in PVC

The pigments 1 to 100 prepared according to Examples 1 to 100 were eachsubjected to a determination of colour strength by the method whichfollows. The results are listed in Table 1.

The test medium produced was a flexible PVC compound, by homogenizing67.5% Vestolit® E7004 (Vestolit GmbH), 29.0% Hexamoll® Dinch (BASF),2.25% Baerostab UBZ 770 (Baerlocher GmbH) and 1.25% Isocolor whitepigment paste (ISL-Chemie) with a laboratory dissolver.

A laboratory roll mill was used to add 100 g of the PVC compound at 150°C. to two rollers of diameter 150 mm that rotate at 20 min⁻¹ and 18min⁻¹. Together with 0.10 g of pigment, the milled sheet that formed wasguided through a roller gap of 0.10 mm eight times. Then thehomogeneously coloured milled sheet was removed with a roller gap of 0.8mm and laid out flat over a metal surface. The cooled milled sheet wasthen passed through a roller gap of 0.2 mm between two unheated rollersof diameter 110 mm that rotate at 26 min⁻¹ and 24 min⁻¹ eight times. Tosmooth the surface, this milled sheet was applied to the rollers at 150°C. once again, removed at 0.8 mm and left to cool on a smooth surface.Specimens of this sheet served to determine the relative colourstrength.

The relative colour strength was calculated after measuring thereflectance of the specimens against a white background by means of aspectrophotometer with d/8 measurement geometry under D65 illuminantwith a 10° observer according to DIN 55986 using the sum total of theK/S values over the visible spectrum (400 nm-700 nm).

TABLE 1 Molar Ni/Zn Colour Status ratio strength % Pigment 1: inventive 14.0:1 121 Pigment 2: inventive  2.0:1 124 Pigment 3: inventive 0.667:1123 Pigment 4: inventive 0.071:1 122 Pigment 5: inventive  14.0:1 125Pigment 6: inventive  2.0:1 124 Pigment 7: inventive 0.667:1 123 Pigment8: inventive 0.071:1 126 Pigment 9: inventive  14.0:1 125 Pigment 10:inventive  2.0:1 126 Pigment 11: inventive 0.667:1 127 Pigment 12:inventive 0.071:1 125 Pigment 13: inventive  14.0:1 124 Pigment 14:inventive  2.0:1 126 Pigment 15: inventive 0.667:1 125 Pigment 16:inventive 0.071:1 126 Pigment 17: inventive  16.0:1 116 Pigment 18:inventive  2.4:1 116 Pigment 19: inventive 0.545:1 114 Pigment 20:inventive 0.063:1 116 Pigment 21: inventive  16.0:1 115 Pigment 22:inventive  2.4:1 115 Pigment 23: inventive 0.545:1 119 Pigment 24:inventive 0.063:1 118 Pigment 25: inventive  16.0:1 115 Pigment 26:inventive  2.4:1 116 Pigment 27: inventive 0.545:1 117 Pigment 28:inventive 0.063:1 118 Pigment 29: inventive  16:0:1 117 Pigment 30:inventive  2.4:1 116 Pigment 31: inventive 0.545:1 115 Pigment 32:inventive 0.063:1 116 Pigment 33: inventive  17.6:1 111 Pigment 34:inventive 2.321:1 110 Pigment 35: inventive 0.938:1 109 Pigment 36:inventive 0.057:1 111 Pigment 37: inventive  17.6:1 110 Pigment 38:inventive 2.321:1 111 Pigment 39: inventive 0.938:1 109 Pigment 40:inventive 0.057:1 111 Pigment 41: inventive  17.6:1 111 Pigment 42:inventive 2.321:1 112 Pigment 43: inventive 0.938:1 113 Pigment 44:inventive 0.057:1 111 Pigment 45: inventive  17.6:1 109 Pigment 46:inventive 2.321:1 112 Pigment 47: inventive 0.938:1 112 Pigment 48:inventive 0.057:1 107 Pigment 49: noninventive  18.4:1 97 Pigment 50:noninventive 2.321:1 99 Pigment 51: noninventive 1.021:1 98 Pigment 52:noninventive 0.054:1 96 Pigment 53: noninventive  18.4:1 98 Pigment 54:noninventive 2.321:1 99 Pigment 55: noninventive 1.021:1 98 Pigment 56:noninventive 0.054:1 99 Pigment 57: noninventive  18.4:1 95 Pigment 58:noninventive 2.321:1 96 Pigment 59: noninventive 1.021:1 99 Pigment 60:noninventive 0.054:1 99 Pigment 61: noninventive  18.4:1 95 Pigment 62:noninventive 2.321:1 96 Pigment 63: noninventive 1.021:1 97 Pigment 64:noninventive 0.054:1 95 Pigment 65: noninventive  12.0:1 94 Pigment 66:noninventive  1.6:1 96 Pigment 67: noninventive 0.625:1 93 Pigment 68:noninventive 0.083:1 95 Pigment 69: noninventive  12.0:1 94 Pigment 70:noninventive  1.6:1 96 Pigment 71: noninventive 0.625:1 96 Pigment 72:noninventive 0.083:1 93 Pigment 73: noninventive  12.0:1 95 Pigment 74:noninventive  1.6:1 96 Pigment 75: noninventive 0.625:1 93 Pigment 76:noninventive 0.083:1 95 Pigment 77: noninventive  12.0:1 96 Pigment 78:noninventive  1.6:1 95 Pigment 79: noninventive 0.625:1 93 Pigment 80:noninventive 0.083:1 95 Pigment 81: noninventive  14.0:1 100 Pigment 82:noninventive  2.0:1 100 Pigment 83: noninventive 0.667:1 100 Pigment 84:noninventive 0.071:1 100 Pigment 85: noninventive  16.0:1 100 Pigment86: noninventive  2.4: 100 Pigment 87: noninventive 0.545:1 100 Pigment88: noninventive 0.063:1 100 Pigment 89: noninventive  17.6:1 100Pigment 90: noninventive 2.321:1 100 Pigment 91: noninventive 0.938:1100 Pigment 92: noninventive 0.057:1 100 Pigment 93: noninventive 18.4:1 100 Pigment 94: noninventive 2.321:1 100 Pigment 95:noninventive 1.021:1 100 Pigment 96: noninventive 0.054:1 100 Pigment97: noninventive  12.0:1 100 Pigment 98: noninventive  1.6:1 100 Pigment99: noninventive 0.625:1 100 Pigment 100: noninventive 0.083:1 100

CONCLUSION

As is apparent from Table 1, all the inventive pigments have elevatedcolour strengths. This means that these pigments, based on equalstarting weights, attain higher optical densities than the noninventivepigments.

What is claimed is:
 1. A metal azo pigment comprising: a) three or moremetal azo compounds which differ at least in the type of metal and whicheach contain structural units of the formula (I), or the tautomericforms thereof,

in which R¹ and R² are each independently OH, NH₂ or NHR⁵, R³ and R⁴ areeach independently ═O or ═NR⁵, R⁵ is hydrogen or alkyl, and Ni²⁺ and/orZn²⁺ ions and at least one further metal ion Me, where Me is a di- ortrivalent metal ion selected from the group of Cu²⁺, Al³⁺, Fe²⁺, Fe³⁺,Co²⁺ and Co³⁺, with the proviso that the amount of Zn²⁺ and Ni²⁺ ionstogether is 70 to 95 mol % and the amount of metal ions Me is 5 to 30mol % based in each case on one mole of all metal ions in the metal azopigment, and the molar ratio of Zn²⁺ to Ni²⁺ ions in the metal azopigment is 92:5 to 5:92, and b) one or more compounds of the formula(II)

in which R⁶ is hydrogen or alkyl.
 2. The metal azo pigments according toclaim 1, wherein: the molar ratio of Zn²⁺ to Ni²⁺ ions in the metal azopigment is 70:10 to 10:70 and more preferably 60:25 to 25:60; the amountof Zn²⁺ and Ni²⁺ ions together is 70 mol % to less than 95 mol % and theamount of metal ions Me is more than 5 mol % to 30 mol %, based in eachcase on one mole of all metal ions in the metal azo pigment; R⁵ ishydrogen or C₁-C₄-alkyl; and R⁶ is hydrogen or C₁-C₄-alkyl optionallymono- or polysubstituted by OH.
 3. The metal azo pigment according toclaim 1, wherein components a) and components b) are present together inthe form of adducts.
 4. The metal azo pigment according to claim 1,wherein: R¹ and R² are OH, R³ and R⁴ are ═O, and R⁶ is hydrogen.
 5. Themetal azo pigment according to claim 1, wherein 0.05 to 4 mol,preferably 0.5 to 2.5 mol, and most preferably 1.0 to 2.0 mol ofcompounds of the formula (II) is present per mole of structural units ofthe formula (I).
 6. The metal azo pigment according to claim 1, whereinthe pigment has a specific surface area of 50 to 200 m²/g, preferably of80 to 160 m²/g, and most preferably of 100 to 150 m²/g.
 7. The metal azopigment according to claim 2, wherein: components a) and components b)are present together in the form of adducts; R¹ and R² are OH; R³ and R⁴are ═O; R⁶ is hydrogen; 0.5 to 2.5 mol, and most preferably 1.0 to 2.0mol of compounds of the formula (II) is present per mole of structuralunits of the formula (I); and the pigment has a specific surface area of80 to 160 m²/g, and most preferably of 100 to 150 m²/g.
 8. A process forproducing the metal azo pigment according to claim 1, the processcomprising contacting: a compound of the formula (III), or tautomersthereof,

in which X is an alkali metal ion, preferably a sodium or potassium ion,R¹ and R² are each independently OH, NH₂ or NHR⁵, R³ and R⁴ are eachindependently ═O or ═NR⁵, and R⁵ is hydrogen or alkyl, preferablyC₁-C₄-alkyl, with at least one compound of the formula (II)

in which R⁶ is hydrogen or alkyl, preferably C₁-C₄-alkyl optionallymono- or polysubstituted by OH, either simultaneously or successivelywith one or more nickel salts, one or more zinc salts, and one or morefurther metal salts selected from the group consisting of Cu²⁺, Al³⁺,Fe²⁺, Fe³⁺, Co²⁺ and Co³⁺ salts, where 0.05 to 0.9 mol of the one ormore nickel salts, 0.05 to 0.9 mol of the one or more zinc salts and0.05 to 0.3 mol, preferably more than 0.05 mol to 0.3 mol, of the one ormore further metal salts from the abovementioned group are used per moleof compound of the formula (III), and the sum total of the molar amountsof all the metal salts used is 100 mol %.
 9. The process according toclaim 8, wherein: X is a sodium or potassium ion, R⁵ is hydrogen orC₁-C₄-alkyl, R⁶ is hydrogen or C₁-C₄-alkyl optionally mono- orpolysubstituted by OH, and more than 0.05 mol to 0.3 mol of the one ormore further metal salts is used per mole of compound of the formula(III).
 10. Pigment preparations comprising the at least one metal azopigment according to claim 1 and one or more auxiliary and/or additive,preferably selected from the group consisting of surface-active agents,surface-covering agents, bases and solvents, and optionally one or morefurther pigment.
 11. The pigment preparation of claim 10, wherein thefurther pigment comprises C.I. Pigment Green 36 and/or C.I. PigmentGreen
 58. 12. A process for producing a pigment preparation comprisingthe at least one metal azo pigment according to claim 1, the processcomprising mixing and/or grinding the at least one metal azo pigmentaccording to claim 1 with at least one auxiliary and/or additive,preferably from the group of surface-active agents, surface-coveringagents, bases and solvents, and optionally with at least one furtherpigment.
 13. A method of use of a metal azo pigment according to claim 1for the colouring of inkjet inks, colour filters for liquid-crystaldisplays, printing inks, distempers or emulsion paints, for the bulkcolouring of synthetic, semisynthetic or natural macromolecularsubstances, especially polyvinyl chloride, polystyrene, polyamide,polyethylene or polypropylene, and for the spin dyeing of natural,regenerated or synthetic fibres, for example cellulose, polyester,polycarbonate, polyacrylonitrile or polyamide fibres, and for printingof textiles and paper.
 14. A colour filter, photoresist, printing ink,or liquid-crystal display comprising one or more metal azo pigmentsaccording to claim
 1. 15. The colour filter, photoresist, printing ink,or liquid-crystal display of claim 14, wherein the at least one metalazo pigment according to claim 1 is a component of a pigment preparationcomprising the at least one metal azo pigment according to claim 1, andat least one auxiliary and/or additive, preferably from the group ofsurface-active agents, surface-covering agents, bases and solvents, andoptionally at least one further pigment.
 16. A photoresist comprisingone or more metal azo pigments according to claim 1, and one or morephotocurable monomers and one or more reaction photoinitiators andoptionally one or more binders or dispersants and/or solvents.
 17. Thephotoresist of claim 16, wherein the at least one metal azo pigment is acomponent of a pigment preparation comprising the at least one metal azopigment, and at least one auxiliary and/or additive, preferably from thegroup of surface-active agents, surface-covering agents, bases andsolvents, and optionally at least one further pigment.
 18. A process forproducing colour filters for liquid-crystal displays, the processcomprising a) applying the photoresist according to claim 16 to asubstrate, b) exposing the photoresist by means of a photomask, c)curing, and d) developing to provide a finished coloured colour filter.